Is it possible to connect 2 serial LCDs to a microcontroller just like in the pic here? http://www.aliexpress.com/item/Free-shipping-New-Blue-IIC-I2C-TWI-1602-Serial-LCD-Module-Display-Arduino-competible/647824738.html The pic has 1 serial lcd connected. Can you connect a second also directly to the microcontroller? and what microcontroller would you need?


You can connect two or more (actually 8 ) LCDs to the Arduino. Any Arduino will do the job. The LCDs you linked to, will not work however as I don't see a way to change the I2C address on them, but this version should work as you can change the address via the A0 - A2 pads. You can buy an LCD and backpack separately and solder it on. Backpack: http://www.ebay.com/itm/111113228045 LCD: http://www.ebay.com/itm/220604499525 Or in one piece, but it's a 20x4: http://www.ebay.com/itm/310575296583 I'm using one of these and it works great.


Thanks for the reply!

What I dont understand, is where on the microcontroller do I connect the second LCD? I want to avoid using breadboard so I want 2 LCD displays directly on the microcontroller. I dont see where the 2nd LCD will go.

I have found some sensor shields like

http://www.emartee.com/product/42015/ scroll down there is a pic with 2 LCDs


or this? http://yourduino.com/sunshop2/index.php?l=product_detail&p=95


I think you can put 2 LCD displays directly to the shields right? I just want to make sure cos Im new to this. Ot maybe there is a way to put 2 LCD displays directly to a Arduino Mega?

Thanks again for your help!

Serial LCDs will share pins. Some LCDs which use the USART connection type can be driven by separate pins using SoftwareSerial.
I2C devices require the I2C bus, which is just two pins on your controller.
If you don’t want to use a breadboard I suggest you construct your own shield, or if it’s an Arduino Uno or Mega, you can probably get away with sticking 2 wires into a single pin header.

OK, on the display you cited first, the address select to distinguish each module is the three jumper positions (6 holes) visible (or partly obscured by the watermark) below the blue potentiometer.

You connect the displays in exact parallel, the same four wires to the same four terminals on each. You need some form of "daisy chaining" wiring - the particular module you illustrate actually has positions to mount (two) extra four-pin headers for such "daisy chaining" from one to the next; you may need to do some soldering or crimping.

You do not need a "sensor shield" to connect them, though if you are using it for other attachments, that might be quite convenient. The second connector shown in the sensor shield picture is connected to to the "serial" spill for a different sort of LCD interface using another two port bits which is not the most sensible in practice.

The I2C LCD library provides for "descriptors" detailing address and interface within the "backpack" to the LCD, you simply generate two descriptors corresponding to the two alternate display modules.